Graft ligament anchor and method for attaching a graft ligament to a bone

ABSTRACT

A graft ligament anchor includes a tubular body having a bore therethrough and proximal and distal ends. A flange is attached to the tubular body at the proximal end thereof and extends radially outwardly beyond the tubular body. A deformable wall is disposed in the tubular body bore and defines, at least in part, a chamber for retaining the graft ligament therein. An expansion device is configured for insertion into the tubular body axially of the tubular body, and for impinging upon the deformable wall to press the deformable wall, and hence the graft ligament received in the chamber, toward a wall of the bore, whereby to fix the graft ligament in the tubular body.

This is a continuation of pending prior U.S. patent application Ser. No.09/248,523, filed Feb. 09, 1999 now abandoned U.S. Pat. No. 6,533,816 byJoseph H. Sklar for GRAFT LIGAMENT ANCHOR AND METHOD FOR ATTACHING AGRAFT LIGAMENT TO A BONE.

FIELD OF THE INVENTION

This invention relates to medical apparatus and methods in general, andmore particularly to apparatus and methods for reconstructing ligaments.

BACKGROUND OF THE INVENTION

Ligaments are tough bands of tissue which serve to connect the articularextremities of bones, or to support and/or retain organs in place withinthe body. Ligaments are typically composed of coarse bundles of densewhite fibrous tissue which are disposed in a parallel or closelyinterlaced manner, with the fibrous tissue being pliant and flexible butnot significantly extensible.

In many cases, ligaments are torn or ruptured as a result of accidents.Various procedures have been developed to repair or replace such damagedligaments.

For example, in the human knee, the anterior and posterior cruciateligaments (i.e., the “ACL” and “PCL”) extend between the top end of thetibia and the bottom end of the femur. The ACL and PCL cooperate,together with other ligaments and soft tissue, to provide both staticand dynamic stability to the knee. Often, the anterior cruciate ligament(i.e., the ACL) is ruptured or torn as a result of, for example, asports-related injury. Consequently, various surgical procedures havebeen developed for reconstructing the ACL so as to restore substantiallynormal function to the knee.

In many instances, the ACL may be reconstructed by replacing theruptured ACL with a graft ligament. More particularly, in suchprocedures, bone tunnels are generally formed in the top end of thetibia and the bottom end of the femur, with one end of the graftligament being positioned in the femoral tunnel and the other end of thegraft ligament being positioned in the tibial tunnel. The two ends ofthe graft ligament are anchored in place in various ways well known inthe art so that the graft ligament extends between the bottom end of thefemur and the top end of the tibia in substantially the same way, andwith substantially the same function, as the original ACL. This graftligament then cooperates with the surrounding anatomical structures soas to restore substantially normal function to the knee.

In some circumstances, the graft ligament may be a ligament or tendonwhich is harvested from elsewhere in the patient; in othercircumstances, the graft ligament may be a synthetic device. For thepurposes of the present invention, all of the foregoing are collectivelyreferred to as a “graft ligament”.

As noted above, the graft ligament may be anchored in place in variousways well known in the art. See, for example, U.S. Pat. No. 4,590,928,issued May 27, 1986 to Michael S. Hunt et al.; U.S. Pat. No. 4,744,793,issued May 17, 1988 to Jack E. Parr et al.; U.S. Pat. No. 4,755,183,issued Jul. 5, 1988 to Robert V. Kenna; U.S. Pat. No. 4,784,126, issuedNov. 15, 1988 to Donald H. Hourahane; U.S. Pat. No. 4,828,562, issuedMay 9, 1989 to Robert V. Kenna; U.S. Pat. No. 4,927,421, issued May 22,1990 to E. Marlowe Goble et al.; U.S. Pat. No. 4,950,270, issued Aug.21, 1990 to Jerald A. Bowman et al.; U.S. Pat. No. 5,062,843, issuedNov. 5, 1991 to Thomas H. Mahony, III; U.S. Pat. No. 5,147,362, issuedSep. 15, 1992 to E. Marlowe Goble; U.S. Pat. No. 5,151,104, issued Sep.29, 1992 to Robert V. Kenna; U.S. Pat. No. 5,211,647, issued May 18,1993 to Reinhold Schmieding; and French Patent Publication No.2,590,792, filed Dec. 4, 1985 by Francis Henri Breard.

Despite the above-identified advances in the art, there remains a needfor a graft ligament anchor which is simple in construction, inexpensiveto manufacture, and relatively easy to handle and install, whileproviding safe and effective anchoring of the graft ligament, typicallyin the knee joint of a mammal.

In addition to the foregoing, it has also been found that the quality ofthe bone receiving the graft ligament can vary significantly frompatient to patient and/or from site to site. In particular, it has beenfound that in many situations, the bone receiving the graft ligament maybe of relatively poor quality, in the sense that the bone is relativelysoft and/or lacking in a consistent structure. This can make itdifficult to easily and reliably anchor the graft ligament to the bone.

Thus, there also exists a need for a graft ligament anchor which caneasily and reliably anchor a graft ligament to a bone of relatively poorquality.

OBJECTS OF THE INVENTION

Accordingly, one object of the present invention is to provide animproved graft ligament anchor which is relatively simple inconstruction, inexpensive to manufacture, and relatively easy to handleand install, and safe and effective in operation.

Another object of the present invention is to provide an improved graftligament anchor which can easily and reliably anchor a graft ligament toa bone of relatively poor quality.

And another object of the present invention is to provide an improvedmethod for attaching a graft ligament to a bone.

SUMMARY OF THE INVENTION

These and other objects of the present invention are addressed by theprovision and use of a novel graft ligament anchor.

In one form of the invention, the graft ligament anchor comprises atubular body having a bore therethrough and proximal and distal ends,the tubular body being adapted for placement in a bone tunnel proximatean opening thereof on a bone surface; stop apparatus connected to thetubular body for preventing movement of the tubular body further intothe bone tunnel after placement of the tubular body in the opening andthe bone tunnel; a deformable wall disposed in the tubular body bore anddefining at least in part a chamber for receiving a graft ligamenttherein; and an expansion device for insertion into the tubular bodyaxially of the tubular body, for impinging upon the deformable wall soas to press the deformable wall, and hence the graft ligament receivedin the chamber, toward a wall of the bore, whereby to fix the graftligament in the tubular body.

In accordance with a further feature of the invention, there is provideda method for securing a graft ligament in a bone tunnel having an endopening on a bone surface, a free end of the graft ligament extendingout of the bone tunnel end opening. The method comprises providing agraft ligament anchor comprising a tubular body having a boretherethrough and proximal and distal ends; stop apparatus connected tothe tubular body for preventing movement of the tubular body furtherinto the bone tunnel after placement of the tubular body in the openingand the bone tunnel; a deformable wall disposed in the tubular body boreand defining at least in part a chamber for receiving the graft ligamenttherein; and an expansion device for insertion into the tubular bodyaxially of the tubular body, for impinging upon the deformable wall soas to press the deformable wall, and hence the graft ligament receivedin the chamber, toward a wall of the bore, whereby to fix the graftligament in the tubular body. The method further comprises the steps ofextending the graft ligament free end through the chamber; placing thetubular body in the bone tunnel end opening and in the bone tunnel suchthat the stop apparatus engages the bone; pulling the graft ligamenttaut; and inserting the expansion device into the tubular body andadvancing the expansion device therein so as to press the deformablewall, and hence the graft ligament received in the chamber, toward thewall of the bore, whereby to fix the graft ligament in the bone tunnel.

In another form of the invention, the graft ligament anchor comprises atubular body having a bore therethrough and proximal and distal ends. Anannular flange is attached to the tubular body at the proximal endthereof and extends radially outwardly beyond the tubular body. Adeformable wall is disposed in the tubular body bore and defines, atleast in part, a chamber for receiving the graft ligament therein. Anexpansion device is adapted for insertion into the tubular body, axiallyof the tubular body, for impinging upon the deformable wall so as topress the deformable wall, and hence the graft ligament received in thechamber, toward a wall of the bore, whereby to fix the graft ligament inthe tubular body.

In accordance with a further feature of the invention, there is provideda method for securing a graft ligament in a bone tunnel having an endopening on a bone surface, a free end of the graft ligament extendingout of the bone tunnel end opening. The method comprises providing agraft ligament anchor comprising a tubular body having a boretherethrough and proximal and distal ends; an annular flange attached tothe tubular body at the proximal end thereof and extending radiallyoutwardly beyond the tubular body; a deformable wall disposed in thetubular body bore and defining at least in part a chamber for receivingthe graft ligament therein; and an expansion device for insertion intothe tubular body axially of the tubular body, for impinging upon thedeformable wall so as to press the deformable wall, and hence the graftligament received in the chamber, toward a wall of the bore, whereby tofix the graft ligament in the tubular body. The method further comprisesthe steps of extending the ligament free end through the chamber;placing the tubular body in the bone tunnel end opening and in the bonetunnel such that the annular flange engages the bone surface; pullingthe graft ligament taut; and inserting the expansion device into thetubular body and advancing the expansion device therein so as to pressthe deformable wall, and hence the graft ligament received in thechamber, toward the wall of the bore, whereby to fix the graft ligamentin the bone tunnel.

In accordance with a further feature of the invention, there is provideda graft ligament anchor comprising a tubular body having a boretherethrough and proximal and distal ends, the tubular body beingadapted for placement in a bone tunnel proximate an opening therefor ona bone surface; stop apparatus connected to the tubular body forpreventing movement of the tubular body further into the bone tunnelafter placement of the tubular body in the tunnel; a carrier device forinsertion into the tubular body axially of the tubular body and havingan external groove therein for receiving a graft ligament, and a centralchannel extending lengthwise therethrough, the carrier being expandable;and an expansion device for insertion into the carrier device channelwhen the carrier device is in the tubular body, for expanding thecarrier device against an internal wall of the tubular body, whereby tofix the graft ligament in the tubular body.

In accordance with a further feature of the invention, there is provideda method for securing a graft ligament in a bone tunnel having an endopening on a bone surface, a free end of the graft ligament extendingout of the bone tunnel end opening, the method comprising the step ofproviding a graft ligament anchor comprising a tubular body having abore therethrough and proximal and distal ends, the tubular body beingadapted for placement in a bone tunnel proximate an opening therefor ona bone surface; stop apparatus connected to the tubular body forpreventing movement of the tubular body further into the bone tunnelafter placement of the tubular body in the tunnel; a carrier device forinsertion into the tubular body axially of the tubular body and havingan external groove therein for receiving a graft ligament, and a centralchannel extending lengthwise therethrough, the carrier being expandable;and an expansion device for insertion into the carrier device channelwhen the carrier device is in the tubular body, for expanding thecarrier device against an internal wall of the tubular body, whereby tofix the graft ligament in the tubular body. The method further includesthe steps of extending the graft ligament free end through the tubularbody; placing the tubular body in the bone tunnel end opening and in thebone tunnel such that the stop apparatus engages the bone; extending theligament free end through the carrier device groove; placing the carrierdevice in the tubular body; pulling the graft ligament taut; andinserting the expansion device into the carrier device and advancing theexpansion device therein to press the carrier device, and hence thegraft ligament received in the groove, toward an internal wall of thetubular body, whereby to fix the graft ligament in the bone tunnel.

In accordance with a further feature of the invention, there is provideda graft ligament anchor comprising a tubular body having a boretherethrough and proximal and distal ends; a flange attached to thetubular body at the proximal end thereof and extending outwardly beyondthe body; a carrier device for insertion into the tubular body axiallyof the tubular body and having a lengthwise-extending external groovefor receiving the graft ligament therein, and a central channelextending lengthwise therethrough, the carrier device having adeformable side wall; and an expansion device for insertion into thecarrier device, when the carrier device is in the tubular body, forimpinging upon the deformable wall of the carrier device so as to pressthe deformable wall, and hence the graft ligament received in thecarrier device groove, toward a wall of the tubular body bore, wherebyto fix the graft ligament in the tubular body.

In accordance with another feature of the invention, there is provided amethod for securing a graft ligament in a bone tunnel having an endopening on a bone surface, a free end of the graft ligament extendingout of the bone tunnel end opening. The method comprises the step ofproviding a graft ligament anchor including a tubular body having a boretherethrough and proximal and distal ends; a flange attached to thetubular body at the proximal end thereof and extending outwardly beyondthe body; a carrier device for insertion into the tubular body axiallyof the tubular body and having a lengthwise-extending exterior groovefor receiving the graft ligament therein, and a central channelextending lengthwise therethrough, the carrier device having adeformable side wall; and an expansion device for insertion into thecarrier device, when the carrier device is in the tubular body, forimpinging upon the deformable wall of the carrier device so as to pressthe deformable wall, and hence the graft ligament received in thecarrier device groove, toward a wall of the tubular body bore, wherebyto fix the graft ligament in the tubular body. The method furtherincludes the steps of extending the graft ligament free end through thetubular body; placing the tubular body in the bone tunnel end openingand in the bone tunnel such that the flange engages the bone surface;extending the graft ligament free end through the carrier device groove;placing the carrier device in the tubular body; pulling the graftligament taut; and inserting the expansion device into the carrierdevice and advancing the expansion device therein so as to press thecarrier device deformable wall, and hence the graft ligament received inthe carrier device groove, toward an interior wall of the tubular body,whereby to fix the graft ligament in the bone tunnel.

In accordance with a further feature of the invention, there is provideda graft ligament anchor comprising a tubular body having a boretherethrough, external threads along a length thereof, and proximal anddistal ends; a carrier device for insertion into the tubular bodyaxially of the tubular body and having a lengthwise-extending externalgroove for receiving the graft ligament therein, and a central channelextending lengthwise therethrough, the carrier device having adeformable side wall; and an expansion device for insertion into thecarrier device, when the carrier device is in the tubular body, forimpinging upon the deformable wall of the carrier device so as to pressthe deformable wall, and hence the graft ligament received in thecarrier device groove, toward a wall of the tubular body bore, wherebyto fix the graft ligament in the tubular body.

In accordance with a further feature of the invention, there is provideda method for securing a graft ligament in a bone tunnel having an endopening on a bone surface, a free end of the graft ligament extendingout of the bone tunnel end opening. The method comprises the step ofproviding a graft ligament anchor comprising a tubular body having abore therethrough, external threads along a length thereof, and proximaland distal ends; a carrier device for insertion into the tubular bodyaxially of the tubular body and having a lengthwise-extending externalgroove for receiving the graft ligament therein, and a central channelextending lengthwise therethrough, the carrier device having adeformable side wall; and an expansion device for insertion into thecarrier device, when the carrier device is in the tubular body, forimpinging upon the deformable wall of the carrier device so as to pressthe deformable wall, and hence the graft ligament received in thecarrier device groove, toward a wall of the tubular body bore, wherebyto fix the graft ligament in the tubular body. The method furthercomprises the steps of extending the graft ligament free end through thetubular body; screwing the tubular body into the bone tunnel end openingand into the bone tunnel; extending the ligament free end through thecarrier device groove; placing the carrier device in the tubular body;pulling the graft ligament taut; and inserting the expansion device intothe carrier device and advancing the expansion device therein so as topress the carrier device deformable wall, and hence the graft ligamentreceived in the groove, toward an interior wall of the tubular body,whereby to fix the graft ligament in the bone tunnel.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will bemore fully disclosed or rendered obvious by the following detaileddescription of the preferred embodiments of the invention, which are tobe considered together with the accompanying drawings wherein likenumbers refer to like parts, and further wherein:

FIG. 1 is a diagrammatic illustration of a ligament anchoringapplication conducted in accordance with one aspect of the presentinvention;

FIG. 2 is an exploded perspective view of one form of graft ligamentanchor illustrative of an embodiment of the invention;

FIG. 3 is an end view of the anchor tubular body portion of FIG. 2;

FIG. 4 is an end view of an alternative embodiment of the anchor tubularbody portion;

FIG. 5 is a perspective view showing another alternative embodiment ofthe anchor tubular body portion;

FIG. 6 is a side elevational view of the tubular body portion embodimentof FIG. 5;

FIG. 7 is a perspective view of another alternative embodiment of theanchor tubular body portion;

FIG. 8 is a side elevational view of the embodiment of FIG. 7, shown inplace in a bone tunnel;

FIG. 8A is a perspective view of another alternative embodiment of theanchor tubular body portion;

FIG. 9 is an exploded perspective view of another alternative embodimentof graft ligament anchor;

FIG. 10 is a sectional view taken along line 10—10 of FIG. 9;

FIG. 11 is similar to FIG. 9, but showing still another alternativeembodiment of ligament anchor;

FIG. 12 is similar to FIG. 11, but showing still another alternativeembodiment of ligament anchor; and

FIG. 13 is a perspective view of an alternative embodiment of the anchortubular body portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIG. 1, it will be seen that in one application ofthe graft ligament anchor, bone tunnels T_(F) and T_(B) are formed in afemur F and tibia B, respectively. A graft ligament L is anchored at oneend (not shown) in the femur F by means well known in the art, andextends from femoral tunnel T_(F) and into tibial tunnel T_(B) andtherethrough. The free end of graft ligament L extending from a tunnelopening P on a tibial surface S must be anchored to tibia B, so thatgraft ligament L is secured at both ends and essentially duplicates thefunction of the aforementioned ACL.

Referring next to FIGS. 1-3, it will be seen that, in one illustrativeembodiment, the inventive graft ligament anchor 10 includes a tubularbody 12 having a bore 14 extending therethrough and having a proximalend 16 and a distal end 18. An annular flange 20 is fixed to tubularbody 12 at proximal end 16 thereof, and extends radially outwardlybeyond body 12. Flange 20 may be continuous, interrupted, or a partialflange, the former being shown in FIGS. 2-8 and the latter being shownin FIG. 9.

One or more deformable walls 22 (four such walls 22 are shown in FIGS. 2and 3) are formed in tubular body bore 14 and define, in conjunctionwith tubular interior body wall 21, elongated chambers 23 which extendlengthwise within tubular body 12. Elongated chambers 23 are eachadapted to receive and retain a graft ligament L therein.

An expansion device 24 (FIG. 2), such as a wedge, wedge-shaped screw orthe like, is adapted for insertion into tubular body 12 axially of thetubular body, for impinging upon deformable walls 22 so as to pressdeformable walls 22, and hence the graft ligament L received in anelongated chamber 23, toward wall 21 of bore 14, whereby to fix graftligament L against wall 21, and thereby to fix graft ligament L intubular body 12.

Tubular body 12 and annular flange 20 may be formed as a single integralunit, preferably of a substantially rigid plastic or metal material.

Tubular body 12 may be provided with one or more openings 26 which maybe in the form of elongated slots (FIGS. 2, 5, 6, 7 and 8) or orifices(FIG. 9). Openings 26 communicate with the interiors of chambers 23 andpermit cells from the bone tunnel walls to migrate into tubular body 12and chambers 23 during the healing process and further lock graftligament anchor 10 and graft ligament L in place in tibial tunnel TB.Furthermore, the openings 26 also serve to receive outwardly-pressedportions of the graft ligament L, which helps to further secure thegraft ligament L to tubular body 12.

In FIG. 4, there is shown an alternative embodiment of graft ligamentanchor 10 in which the deformable walls 22 comprise sleeves 22 adefining elongated chambers 23 for receiving and retaining graftligament L.

Referring next to FIGS. 5 and 6, it will be seen that, in an alternativeembodiment of graft ligament anchor 10, the axis x—x of tubular body 12intersects a plane y—y of annular flange 20 at an acute angle z. Theangle z permits flange 20 to lie flat against the tibial surface S,which surface S is typically not normal to the longitudinal axis oftunnel TB in ACL reconstructions. Tubular body 12 may be provided withthe aforementioned openings or slots 26, as shown in FIGS. 5 and 6.

Referring next to FIGS. 7 and 8, it will be seen that in anotheralternative embodiment of graft ligament anchor 10, arms 28, 30 extendaxially and proximally from tubular body proximal end 16. Annular flange20 is mounted on the proximal ends of arms 28, 30. The arms 28, 30,being of relatively thin structure, provide a degree of flexibility,even if made in unitary fashion as extensions of tubular body 12, andpermit annular flange 20 to assume a position essentially flat againsttibial surface S, while tubular body 12 extends into bone tunnel T_(B)at an acute angle to the plane of flange 20. Again, as seen in FIG. 8,tubular body 12 of this embodiment of graft ligament anchor 10 may beprovided with openings 26 for migration of bone material therethrough.

Referring next to FIG. 8A, it will be seen that in another alternativeembodiment of graft ligament anchor 10, the annular flange 20 ispivotally connected to arms 28, 30 by means of a pair of pins 31. Thisconstruction permits arms 28, 30 to be formed relatively thick andrigid, yet permits annular flange 20 to assume a position essentiallyflat against tibial surface S while tubular body 12 extends into bonetunnel T_(B) at an acute angle to the plane of flange 20.

In essence, with the embodiment of FIGS. 7 and 8, deflection of arms28,30 permits flange 20 to assume the desired position relative totubular body 12, whereas with the embodiment of FIG. 8A, pivot pins 31permit flange 20 to assume the desired position relative to tubular body12.

In operation, the graft ligament L is first anchored in the femur F inways well known in the art, and extended out through tunnels T_(F) andT_(B), and out the tunnel opening P. Then the graft ligament L is fedthrough one of the elongated chambers 23 of tubular body 12. Tubularbody 12 is then inserted into tunnel T_(B) by way of opening P, andadvanced in tunnel T_(B) until flange 20 engages bone surface S. Theengagement of flange 20 with bone surface S will prevent tubular body 12from advancing further into tibia B. The graft ligament L, which extendsout of proximal end 16 of tubular body 12, is then pulled taut, andexpansion device 24 is advanced into bore 14, engaging deformable walls22 (or, alternatively, deformable walls 22 a) and pressing thedeformable walls, and hence the graft ligament L received within one ofthe elongated chambers 23, toward the interior wall of bore 14. Inasmuchas tubular body 12 is relatively rigid, deformable walls 22 compressagainst the bore wall and hold the graft ligament in that position.

At this point, graft ligament L will be securely fastened to bone B,inasmuch as (1) expansion device 24 holds graft ligament L securely totubular body 12, (2) annular flange 20 prevents tubular body 12 frombeing pulled further into tibia bone B, and (3) the graft ligament Lprevents tubular body 12 from falling out of bone tunnel T_(B). In thisrespect it should be appreciated that, inasmuch as graft ligament L istypically slightly elastic in nature, and inasmuch as graft ligament Lis pulled taut prior to fastening to tubular body 12, graft ligament Lwill tend to hold tubular body 12 in bone tunnel T_(B) under tension.

The free end of graft ligament L can then be trimmed off at tibialsurface S.

It should be appreciated that once expansion device 24 has been fullyinserted into tubular body 12, and once the free end of graft ligament Lhas been trimmed off at tibial surface S, only annular flange 20 willprotrude above tibial surface S. Since annular flange 20 is relativelythin, graft ligament anchor 10 has a low profile relative to tibialsurface S. This can be important for patient comfort, particularlyinasmuch as relatively little tissue overrides this portion of thepatient's tibia.

If the graft ligament anchor is provided with openings 26, cells fromthe bone tunnel wall can, during the healing process, migrate throughopenings 26 and into chambers 23 so as to further lock the tubular bodyand graft ligament in place.

It should be appreciated that the deformable walls 22 (or,alternatively, the deformable walls 22 a) of chambers 23 serve toprotect the graft ligament L from cutting or other damage by expansiondevice 24, spread the pressure from expansion device 24 substantiallyevenly on the graft ligament L, and provide improved friction againstthe graft ligament.

It should also be appreciated that, inasmuch as expansion device 24fastens graft ligament L to tubular body 12, and inasmuch as thestructural integrity of tubular body 12 can be carefully controlledduring the manufacturing process, graft ligament anchor 10 will form asecure attachment even when tibia B has relatively poor bone quality.

It should also be appreciated that, inasmuch as a plurality of elongatedchambers 23 are provided in tubular body 12, graft ligament anchor 10can be used to simultaneously fasten a plurality of graft ligament freeends to tibia B.

In FIG. 9, there is shown an alternative embodiment of graft ligamentanchor in which flange 20 is a partial flange, deformable walls 22 areomitted from the interior of tubular body 12, and openings 26 in tubularbody 12 are in the form of a multitude of orifices. This embodimentincludes a ligament carrier 32 having lengthwise-extending grooves 34formed therein for receiving the graft ligament L which is to beanchored. The grooves 34 each may be provided with widthwise-extendingridges 35 which assist in holding the graft ligament L in a groove 34.Expansion device 24, in this embodiment, is preferably a screw which isdriven into a central channel 36 (FIGS. 9 and 10) of ligament carrier32. The distal end 38 of ligament carrier 32 is provided with slits 40which permit expansion of ligament carrier 32. Furthermore, as shown inFIG. 10, central channel 36 and outer grooves 34 define thin walls 42which can expand against a graft ligament L received in an outer groove34, thereby pressing the graft ligament against the interior wall oftubular body bore 14.

If desired, the tubular bodies 12 may also be provided with interiorridges, such as the interior ridges 39 shown in FIG. 5 or correspondingridges (not shown) for the embodiment of FIG. 9, disposed on theinterior wall of tubular body bore 14, for enhanced engagement with thegraft ligament L pressed thereagainst.

Preferably, ligament carrier 32 is provided with a detent 48 extendingoutwardly from the ligament carrier and disposed near a proximal end 50of the ligament carrier. Where tubular body 12 is to be used inconjunction with the ligament carrier 32, tubular body 12, at itsproximal end 16, is provided with a recess 52 which is complementary todetent 48 and adapted to receive the detent, so as to limit advancementof ligament carrier 32 into tubular body 12.

Preferably, but not necessarily, the length of ligament carrier 32exceeds the length of tubular body 12, such that when ligament carrier32 is fully engaged with tubular body 12, a distal portion of ligamentcarrier 32 extends beyond the distal end of tubular body 12.

In operation, graft ligament L is first anchored in femur F and extendedout through tunnels TF and TB and out tunnel opening P. Then graftligament L is fed through tubular body 12. Next, tubular body 12 isinserted into tunnel TB until flange 20 engages bone surface S (FIG. 9).Then graft ligament L is positioned in one of the outer grooves 34 ofligament carrier 32. Ligament carrier 32 is then inserted into bore 14of tubular body 12 until the distal end portion of ligament carrier 32protrudes distally from the distal end of tubular body 12 and carrierdetent 48 engages tubular member recess 52, which prevents furtheradvancement of ligament carrier 32 into tubular body 12. Graft ligamentL, which extends out of ligament carrier 32 and tubular body 12, is thenpulled taut, and expansion device 24 is advanced into the ligamentcarrier's channel 36, engaging deformable walls 42 and pressing thewalls 42, and hence the graft ligament L received in one of the ligamentcarrier's outer grooves 34, toward the interior wall of bore 14.Inasmuch as tubular body 12 is relatively rigid, deformable walls 42compress against the interior bore wall of tubular body 12 and hold thegraft ligament in that position. At the same time, flange 20 preventstubular body 12 from being pulled further into tibia B, and the graftligament prevents tubular body 12 from falling out of bone tunnel T_(B).In this respect it should be appreciated that, inasmuch as graftligament L is slightly elastic in nature, and inasmuch as graft ligamentL is pulled taut prior to fastening to tubular body 12, graft ligament Lwill tend to hold tubular body 12 in bone tunnel T_(B) under tension.

The free end of graft ligament L can then be trimmed off at tibialsurface S.

It should be appreciate that, with the foregoing construction, distallyof the distal end of tubular body 12, ligament carrier 32 presses thegraft ligament directly against interior walls of tibial tunnel TB.Thus, graft ligament L is effectively locked to tubular body 12 and isalso pressed directly against the walls of tibial tunnel T_(B) distal totubular body 12. This arrangement provides a stress transition for graftligament L inasmuch as the graft ligament is held in tubular body 12under relatively high stress, is held under less stress by ligamentcarrier 32 in tibial tunnel T_(B) immediately distally of tubular body12 and, distally of ligament carrier 32, is not pressed against tibialtunnel T_(B). This transitional arrangement provides improved graftstabilization and immobilization, and helps minimize abrasive movementof the graft ligament against bone surfaces during knee flexure.Furthermore, by providing an enhanced region of direct contact betweengraft ligament L and the walls of the bone tunnel, biological fixationof the graft ligament to the bone will be enhanced.

It should also be appreciated that once expansion device 24 has beenfully inserted into ligament carrier 32, and once the free end of graftligament L has been trimmed off at tibial surface S, only annular flange20 will protrude above tibial surface S. Again, since annular flange 20is relatively thin, graft ligament anchor 10 has a low profile relativeto tibial surface S. This can be important for patient comfort,particularly inasmuch as relatively little tissue overrides this portionof the patient's tibia.

It should also be appreciated that, inasmuch as expansion device 24fastens graft ligament L to tubular body 12, and inasmuch as thestructural integrity of tubular body 12 can be carefully controlledduring the manufacturing process, the graft ligament anchor shown inFIGS. 9 and 10 will form a secure attachment even when tibia B hasrelatively poor bone quality.

It should also be appreciated that, inasmuch as a plurality oflengthwise-extending grooves 34 are provided in ligament carrier 32, thegraft ligament anchor can be used to simultaneously fasten a pluralityof graft ligament free ends to tibia B.

Cells from the bone tunnel wall, in due course, can thereafter migratethrough openings 26, and around the graft ligament, so as to furtherlock tubular body 12 and graft ligament L in place.

In FIG. 11, there is shown another alternative embodiment of graftligament anchor, generally similar to the embodiment shown in FIG. 9,but having tubular body portion 12 provided with external screw threads44 rather than flange 20. The embodiment of FIG. 11 is used in much thesame manner as the embodiment of FIG. 9, except that before graftligament L is anchored in femur F, tubular body 12 is screwed into bonetunnel T_(B). To facilitate the screwing rotation, tubular body 12 maybe provided with slots 46 for receiving a screw driver (not shown).Ligament carrier 32 is provided with one or more detents 48 which is/arecomplementary to slots 46, and received by slots 46, so as to limitadvancement of ligament carrier 32 into tubular body 12. The tubularbody 12 may be provided with interior ridges, of the type illustrated inFIG. 5, to assist in the fixation of the graft ligament L to tubularbody 12. And tubular body 12 may be provided with openings 26 to permitcells from the bone tunnel walls to migrate into tubular body 12 and toreceive outwardly-pressed portions of the graft ligament L, in themanner previously discussed.

In operation, the tubular body 12 is screwed into bone tunnel T_(B)until proximal end 16 is inboard of bone surface S. Inasmuch as theposition of threaded tubular body 12 is easily controlled and unlikelyto migrate in the bone tunnel, there is no need for a flange, such asflange 20. Once tubular body 12 is in place, the graft ligament isanchored in the femoral tunnel T_(F) and the remainder of the operationproceeds substantially as set forth above relative to the embodiment ofFIG. 9.

In FIG. 12, there is shown still another alternative embodiment of graftligament anchor, similar to the embodiments of FIGS. 9 and 11, butwherein the expansion device 24 comprises a mandrel 56, rather than ascrew device. The mandrel 56 may be deployed by a gun (not shown) intothe carrier 32 and may be provided with ridges 58 for engaging the wallsof channel 36 of carrier 32, which walls may include opposing ridges toprevent withdrawal of mandrel 56 from channel 36. Otherwise, theassembly of FIG. 12 is used in much the same manner as the assemblies ofFIGS. 9 and 11.

With the embodiments in FIGS. 11 and 12, external screw threads 44prevent tubular body 12 from being pulled further into bone tunnel T_(B)under the tension of graft ligament L. To that extent, external screwthreads 44 serve the same purpose that external flange 20 serves withthe embodiments of FIGS. 1-8, 8A and 9. In this respect it will beappreciated that with the embodiments of FIGS. 11 and 12, once expansiondevice 24 has been fully inserted into ligament carrier 32, and once thefree end of graft liagment L has been trimmed off at tibial surface S,substantially none of the graft ligament anchor will protrude abovetibial surface S. This can be important for patient comfort, inasmuch asrelatively little tissue overrides this portion of the patient's tibia.

The tubular body 12 shown in FIGS. 2-9 may be substantially rigid or maybe slightly expandable to enable the tubular body to more snugly engagethe bone when expansion device 24 is set within the tubular body. In thelatter case, the expansion capability may be provided for by having thetubular body 12 formed out of a plastic material, or by providing, in anotherwise substantially rigid body, a mechanical means for permittingexpansion. In this latter regard, there is shown in FIG. 13 a tubularbody 12 having opposed lengthwise free edges 60, 62 having tongues 64and grooves 66 formed thereon, respectively. Limited expansion of thetubular body 12 is permitted within the confines of thetongue-and-groove arrangement.

It should be appreciate that, by providing (1) tubular body 12, and (2)an external flange 20 or external screw threads 44 for stabilizingtubular body 12 relative to the adjacent bone, and (3) deformable walls22, 22 a, or ligament carrier 32, and expansion device 24 for making thegraft ligament fast to tubular body 12, the graft ligament L can besecurely attached to a host bone. This is true regardless of whethersuch attachment is to relatively hard outer cortical bone, or torelatively soft inner cancellous bone, or even where the host bone hasrelatively poor bone quality.

It should also be appreciated that, while in the foregoing descriptionthe graft ligament anchor of the present invention has been discussed inthe context of attaching one end of a graft ACL to the tibia, the graftligament anchor could also be used to attach one end of the graft ACL tothe femur, or to attach a graft ligament to another bone in the body.

It should also be appreciated that, with respect to the graft ligamentanchor shown in FIGS. 9-12, ligament carrier 32 might be omittedaltogether, and expansion device 24 might be used to attach the graftligament L directly to the side wall of tubular body 12. Of course, insuch a situation, since expansion device 24 will be directly engaginggraft ligament L, it is important that expansion device 24 beconstructed so that it will not cut or otherwise damage graft ligamentL. In such a situation, expansion device 24 might comprise a so-called“non-cutting interference screw” of sort manufactured by Arthrex.

Furthermore, it should also be appreciated that, with respect to thegraft ligament anchor embodiments shown in FIGS. 9-12, tubular body 12might be omitted altogether, and ligament carrier 32 might be used toattach the graft ligament L directly to the side wall of the bonetunnel. Of course, in such a situation, the attachment of the graftligament L to the host bone might be somewhat less secure than wheretubular body 12 is used, particularly where the host bone is relativelysoft cancellous bone or where the host bone is of relatively poor bonequality. Furthermore, in such a situation, it might be desirable toincrease the size of the ligament carrier's detents 48 so that they canact as stops to prevent the ligament carrier from being drawn into thebone tunnel due to ligament tension.

Thus there is provided an improved graft ligament anchor which is simplein construction, inexpensive to manufacture, easy to handle and install,and reliable and safe in operation.

In addition, the graft ligament anchor can easily and reliably anchor agraft ligament in a bone of relatively poor quality.

There is further provided an improved method for attaching a graftligament to a bone.

It is to be understood that the present invention is by no means limitedto the particular constructions and methods herein disclosed and/orshown in the drawings, but also comprises any modifications orequivalents within the scope of the claims. For example, in illustrativeembodiments described hereinabove, ligament carrier 32 is illustratedwith external ridges 35 (FIG. 9), tubular body 12 is illustrated withinterior ridges 39 (FIG. 5), an expansion device 24 is provided withridges 58 (FIG. 12). It will be apparent to those skilled in the artthat such ridges effect a gripping facility by virtue of providing atextured surface. Appropriate and useful surfaces may be rendered“textured” by means other than, or in addition to, ridges, such as bylands, grooves, steps, teeth, apertures, roughened portions, and thelike. Among other things, it has been found that graft ligament fixationcan be improved where such textured surfaces cause the graft ligament toassume a somewhat convoluted or tortuous path on a localized basis,e.g., as the graft ligament extends over a series of adjacent ridges.

1. A graft ligament anchor comprising: a tubular body having a boretherethrough and proximal and distal ends; an annular flange attached tosaid tubular body at the proximal end thereof and extending radiallyoutwardly beyond said body; a deformable wall mounted on an insidesurface of the tubular body bore and in conjunction with the tubularbody inside surface defining a chamber extending lengthwise of saidtubular body for receiving a graft ligament therein; and an expansiondevice for insertion into said tubular body, axially of said tubularbody, for impinging upon said deformable wall so as to press saiddeformable wall, and hence the graft ligament received in the chamber,toward the tubular body inside surface, whereby to fix the graftligament in said tubular body.
 2. A graft ligament anchor according toclaim 1 wherein said graft ligament anchor comprises a furtherdeformable wall, each of said deformable walls defining in part of achamber, each of the chambers being adapted to retain a graft ligamenttherein.
 3. A graft ligament anchor according to claim 2 wherein saidexpansion device comprises a wedge-shaped device for insertion betweenopposed ones of said deformable walls so as to press said opposeddeformable walls outwardly from each other and toward the inside surfaceof the bore.
 4. A graft ligament anchor according to claim 3 whereinsaid wedge-shaped device comprises a screw.
 5. A graft ligament anchoraccording to claim 1 wherein said tubular body is provided with anopening extending through a side of said body and said chamber.
 6. Agraft ligament anchor according to claim 5 wherein said openingcomprises an elongated slot.
 7. A graft ligament anchor according toclaim 1 wherein a pair of arms extend axially and proximally from theproximal end of said body, and said annular flange is fixed to proximalends of said arms.
 8. A graft ligament anchor according to claim 7wherein said body is provided with an opening through a side wallthereof and extending into the chamber.
 9. A graft ligament anchoraccording to claim 1 wherein said expansion device is adapted to pressthe graft ligament in the chamber against the inside surface of thetubular body bore.
 10. A graft ligament anchor according to claim 1wherein said tubular body is provided with interior ridges disposed onthe inside surface of the bore.
 11. A graft ligament anchor according toclaim 1 wherein said tubular body is expandable width-wise.
 12. A graftligament anchor according to claim 3 wherein said wedge-shaped device isprovided with a textured surface.
 13. A graft ligament anchor accordingto claim 3 wherein said wedge-shaped device comprises a mandrel.
 14. Amethod for securing a graft ligament in a bone tunnel having an endopening on a bone surface, a free end of the graft ligament extendingout of the bone tunnel end opening, the method comprising the steps of:providing a graft ligament anchor comprising: a tubular body having abore therethrough and proximal and distal ends, said tubular body beingadapted for placement in a bone tunnel proximate an opening thereof on abone surface; stop apparatus connected to said tubular body forpreventing movement of said tubular body further into the bone tunnelafter placement of said tubular body in the opening and the bone tunnel;and an expansion device for insertion into said tubular body axially ofsaid tubular body, for impinging upon the graft ligament so as to pressthe graft ligament toward the tubular body, whereby to fix the graftligament in the tubular body; extending the graft ligament free endthrough said tubular body; placing said tubular body in the end openingand in the bone tunnel such that said stop apparatus engages the bone;pulling the graft ligament taut; and inserting said expansion deviceinto said tubular body and advancing said expansion device therein topress the graft ligament toward the wall of the bore, whereby to fix thegraft ligament in the bone tunnel.
 15. A graft ligament anchorcomprising: a tubular body having a bore therethrough ad proximal anddistal ends; an annular flange attached to said tubular body at theproximal end thereof and extending radially outwardly beyond said body;a plurality of deformable walls, each defining at least in part achamber, each of the chambers being adapted to retain a graft ligamenttherein; an expansion device for insertion into said tubular body,axially of said body, for impinging upon said deformable walls so as topress said deformable walls, and hence the graft ligaments received inthe chambers, toward a wall of the bore, whereby to fix the graftligament in the tubular body; wherein said expansion device comprises awedge-shaped screw for insertion between opposed ones of said deformablewalls so as to press said opposed deformable walls outwardly from eachother and toward the wall of the bore.
 16. A graft ligament anchoraccording to claim 15 wherein said tubular body is provided withopenings, each extending through a side of said body and a chamber. 17.A graft ligament anchor according to claim 16 wherein the openings eachcomprise an elongated slot.
 18. A graft ligament anchor comprising: atubular body having a bore therethrough and proximal and distal ends; anannular flange attached to said tubular body at the proximal end thereofand extending radially outwardly beyond said body; a deformable walldisposed in the tubular body bore and defining, at least in part, achamber for receiving a graft ligament therein; and an expansion devicefor insertion into said tubular body, axially of said body, forimpinging upon said deformable wall so as to press said deformable wall,and hence the graft ligament received in the chamber, toward a wall ofthe bore, whereby to fix the graft ligament in the tubular body; whereina pair of arms extend axially and proximally from the proximal end ofsaid body, and said annular flange is fixed to proximal ends of saidarms; and wherein said body is provided with an opening through a sidewall thereof and extending into the chamber.
 19. A graft ligament anchorcomprising: a tubular body having a bore therethrough and proximal anddistal ends; an annular flange attached to said tubular body at theproximal end thereof and extending radially outwardly beyond said body;a deformable wall disposed in the tubular body bore and defining, atleast in part, a chamber for receiving the graft ligament therein; andan expansion device for insertion into said tubular body, axially ofsaid body, for impinging upon said deformable wall so as to press saiddeformable wall, and hence the graft ligament received in the chamber,toward a wall of the bore, whereby to fix the graft ligament in saidtubular body; wherein said tubular body is provided with interior ridgesdisposed on the wall of the bore.
 20. A graft ligament anchorcomprising: a tubular body having a bore therethrough and proximal anddistal ends; an annular flange attached to said tubular body at saidproximal end thereof and extending radially outwardly beyond said body;deformable walls, each defining at least in part a chamber, each of thechambers being adapted to retain a graft ligament therein; an expansiondevice for insertion into said tubular body, axially of said body, forimpinging upon said deformable walls so as to press said deformablewalls, and hence the graft ligaments received in the chambers, toward awall of the bore, whereby to fix the graft ligaments in the tubularbody; wherein said expansion device comprises a wedge-shaped device forinsertion between opposed ones of said deformable walls so as to presssaid opposed deformable walls outwardly from each other and toward thewall of the bore; and wherein said wedge-shaped device is provided witha textured surface.
 21. A graft ligament anchor comprising: a tubularbody having a bore therethrough and proximal and distal ends; an annularflange attached to said tubular body at said proximal end thereof andextending radially outwardly beyond said body; deformable walls, eachdefining at least in part a chamber, each of the chambers being adaptedto retain a graft ligament therein; an expansion device for insertioninto said tubular body, axially of said body, for impinging upon saiddeformable walls so as to press said deformable walls, and hence thegraft ligaments received in said chambers, toward a wall of said bore,whereby to fix the graft ligament in the tubular body; wherein saidexpansion device comprises a wedge-shaped device for insertion betweenopposed ones of said deformable walls so as to press said opposeddeformable walls outwardly from each other and toward said wall of saidbore; and wherein said wedge-shaped device comprises a mandrel.